75b2645e3f
git-svn-id: https://yap.svn.sf.net/svnroot/yap/trunk@1580 b08c6af1-5177-4d33-ba66-4b1c6b8b522a
56 lines
862 B
Plaintext
56 lines
862 B
Plaintext
=================================================================
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Logtalk - Object oriented extension to Prolog
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Release 2.27.1
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Copyright (c) 1998-2006 Paulo Moura. All Rights Reserved.
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=================================================================
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% start by loading the example:
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| ?- logtalk_load(operators(loader)).
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...
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% operators declared inside an object are not visible outside:
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| ?- double::(I double J).
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Syntax error: Operator expected
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% you must use instead functor notation:
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| ?- double::double(I, J).
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I = 1
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J = 2 ;
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I = 2
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J = 4 ;
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I = 3
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J = 6
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Yes
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% operators also affect inputing of terms, enabling this example to work:
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| ?- triple::triple(I, J).
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I = 1
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J = 3 ;
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I = 2
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J = 6 ;
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I = 3
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J = 9
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Yes
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% check the file "previous.txt" generated from the file "next.txt" by the object "reverse"
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% by opening the files on a text editor
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